Department of Prenatal Diagnostic Center, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, Guangdong, China.
Hum Genet. 2021 Feb;140(2):333-348. doi: 10.1007/s00439-020-02200-z. Epub 2020 Jul 21.
To explore mutations in the additional sex combs-like 3 (ASXL3) gene in two Chinese families with congenital heart disease (CHD). Whole-exome sequencing (WES) was used to reveal a novel compound heterozygous mutation in the ASXL3 gene that was associated with CHD. Sanger sequencing of a further 122 CHD patients was used to determine an additional compound heterozygous mutation in the ASXL3 gene. Cell apoptosis was examined by MTS assay and flow cytometry. The cardiac structure was identified via hematoxylin-eosin (HE), Masson's trichrome, and ultrasound scanning. RNA sequencing was performed to identify a series of differentially expressed mRNAs. The mRNA and protein expressions were identified by quantitative real-time PCR and western blotting, respectively. A compound heterozygous mutation c.2168C > G (p.Pro723Arg) and c.5449C > G (p.Pro1817Ala) in the ASXL3 gene associated with CHD was identified. Overexpression of this compound heterozygous mutation in HL-1 cells resulted in increased apoptosis and reduced cell viability. Moreover, it affected cardiac structure and fibrosis in mice. There were 126 downregulated mRNAs and 117 upregulated mRNAs between the ASXL3 compound heterozygous mutation c.2168C > G (p.Pro723Arg) and c.5449C > G (p.Pro1817Ala) mice and wild-type mice. Ezh2, Slc6a4, and Socs3, which could interact with ASXL3 through proteins, were all upregulated. Another compound heterozygous mutation c.3526C > T (p.Arg1176Trp) and c.4643A > G (p.Asp1548Gly) in the ASXL3 gene was identified by screening a further 122 patients with CHD. The ASXL3 gene is important in cardiac development and may exert this influence by affecting the expression of mRNAs associated with cell apoptosis and cell proliferation.
探讨 2 个先天性心脏病（CHD）家系中额外的性别梳样 3（ASXL3）基因突变。采用外显子组测序（WES）揭示与 CHD 相关的 ASXL3 基因的新型复合杂合突变。对另外 122 例 CHD 患者进行 Sanger 测序，以确定 ASXL3 基因的另一个复合杂合突变。通过 MTS 测定和流式细胞术检测细胞凋亡。苏木精-伊红（HE）、Masson 三色和超声扫描鉴定心脏结构。进行 RNA 测序以鉴定一系列差异表达的 mRNAs。通过定量实时 PCR 和 Western blot 分别鉴定 mRNA 和蛋白质表达。鉴定出与 CHD 相关的 ASXL3 基因的复合杂合突变 c.2168C>G（p.Pro723Arg）和 c.5449C>G（p.Pro1817Ala）。HL-1 细胞中该复合杂合突变的过表达导致细胞凋亡增加和细胞活力降低。此外，它还影响了小鼠的心脏结构和纤维化。ASXL3 复合杂合突变 c.2168C>G（p.Pro723Arg）和 c.5449C>G（p.Pro1817Ala）与野生型小鼠之间有 126 个下调的 mRNAs 和 117 个上调的 mRNAs。可以通过蛋白质与 ASXL3 相互作用的 Ezh2、Slc6a4 和 Socs3 均上调。通过筛查另外 122 例 CHD 患者，鉴定出 ASXL3 基因的另一个复合杂合突变 c.3526C>T（p.Arg1176Trp）和 c.4643A>G（p.Asp1548Gly）。ASXL3 基因在心脏发育中很重要，可能通过影响与细胞凋亡和细胞增殖相关的 mRNAs 的表达来发挥这种影响。
